IV. Diatonic Harmony, Tonicization, and Modulation
Strengthening Endings with Strong Predominants
John Peterson
Key Takeaways
This chapter introduces two strong predominants: IV and ii6.
- Both harmonize fa [latex](\hat{4})[/latex] in the bass.
- They typically precede a dominant chord and predict that a dominant chord is on its way.
- The most common part-writing error when using strong predominants is parallel octaves or fifths.
As we noted in the Introduction to Harmony, Cadences, and Phrase Endings chapter, most phrase endings are strengthened using a strong predominant (PD) that comes before the V chord ( ). Another way to say this is that it’s common for a phrase to end with the bass pattern fa–sol [latex](\hat4 - \hat5)[/latex] in a half cadence (HC) or fa–sol–do [latex](\hat4 - \hat5 - \hat1)[/latex] in an authentic cadence (AC). The fa [latex](\hat{4})[/latex] in the bass just before a cadence is the note that typically gets harmonized with a strong predominant ( )—these chords are ii6 (the more common option) and IV.
Writing with ii6
The strong predominant area adds a degree of challenge to writing because it’s where parallel octaves and fifths tend to show up (
). You’ll want to carefully check your writing around strong predominants for parallels. One thing that can help is to make as many upper voices as possible in contrary motion with the bass. Since the bass will move up from fa to sol [latex](\hat{4}-\hat5)[/latex], that means it’s best to move your upper voices down. Below are the steps for writing an authentic cadence. Note that if you want to write a half cadence, you just leave off the I chord at the end.
Steps for writing with ii6
- Write the entire bass: fa–sol–do [latex](\hat4 - \hat5 - \hat1)[/latex].
- Write the entire soprano:
- Start with the V chord, and place an active note in the soprano.
- Resolve the active note appropriately over I.
- Approach the active note from above to make contrary motion with the bass, or by common tone.
- Fill in the inner voices by asking “What do I have? What do I need? How should these voices move to create smooth motion and avoid parallels?”
- In ii6, since it’s a first inversion chord, remember that you may double any note that gives you the smoothest voice leading and that avoids parallels.
This process is illustrated in
.
Writing with IV
The danger of writing parallels is even greater with IV than with ii6 because of the root motion by step. Avoid doing something like , where all voices move upward in parallel motion. Just as with ii6, if you make your upper voices move in contrary motion to the bass (down) where possible, you’ll avoid the problem.
The steps for writing with IV are the same as those for ii6: write the entire bass, write the entire soprano starting with V and working outward, then fill in the inner voices (
). There’s one important difference with respect to doubling: whereas the ii6 chord’s doubling is quite flexible since it’s a first-inversion chord, the IV chord almost always sees its bass doubled since it’s a root-position chord.
Root position ii
The ii chord in root position is much less common than ii6 or IV, but it can be used as a strong predominant in major keys. (In minor keys, the iio chord, like any diminished triad, doesn’t normally show up in root position.)
While it’s possible to write parallels with ii, it’s less likely than with IV or ii6.
shows some common options. Note that it’s most common to place re or fa [latex](\hat2[/latex] or [latex]\hat4)[/latex], not la [latex](\hat6)[/latex], in the soprano over ii.
Using IV and ii(6) in combination
Sometimes a composer will choose to use both IV and ii(6) before the dominant at a phrase ending. In such cases, ii always comes after IV. Although both IV and ii(6) are strong pre-dominants, ii(6) shares a special relationship with the V chord that follows: the root of ii is a fifth away from the root of V, similar to how the root of V is a fifth away from the root of I (
). This root relationship makes ii a stronger predominant than IV, which is why ii always comes after IV, never before IV, when both are used at a phrase ending.
- Strengthening Endings with Strong Predominants (.pdf, .docx). Includes part writing from Roman numerals and figures, analysis of phrase endings, and a discussion question about a number from Hamilton.
Predominant function chords are those that transition away from tonic function toward dominant function.
A kind of inconclusive cadence that occurs when a phrase ends on V. Occasionally, particularly in Romantic music, the final chord of a half cadence will be V⁷.
A cadence with the harmonies V–I. The harmonies are typically in root position. Authentic cadences can be further distinguished by their melody note in the I chord: an authentic cadence ending on 1̂ in the melody is a perfect authentic cadence, while one with 3̂ or 5̂ in the melody is an imperfect authentic cadence.
In tonal music, a note that has a tendency to move to a specific note in the following chord, usually a step up or down. Also called a "tendency tone."
A tone that is present in more than one chord.
The distance between roots of adjacent chords. For example, "root motion by step" refers to the distance between two chords that are only one step apart, such as I and ii, IV and V, etc. Note that the root is not always in the bass, so this is a separate concept from bass motion.